Page 204 - Formulas and Calculations for Petroleum Engineering

Well test analysis formulas and calculations Chapter 3 197

m: Viscosity of Oil (cP)
Ø: Porosity (fraction)
c t : Compressibility (1/psi)

Output(s)

r i : Radius of investigation (ft)

Formula(s)

0:5

t
r ¼ k*
i
948 Ø m c
t
Reference: Pressure Buildup and Flow Tests in Wells, Matthews & Russell, Page: 116.

3.48 Radius of investigation (shut-in time)

Input(s)
dt: Time of shut in (h)
k: Permeability (mD)
m: Viscosity of Oil (cP)
Ø: Porosity (fraction)
c t : Compressibility (1/psi)

Output(s)

r i : Radius of investigation (ft)

Formula(s)

0:5
dt
r ¼ k*
i
948 Ø m c
t
Reference: Pressure Buildup and Flow Tests in Wells, Matthews & Russell, Page: 117.

3.49 Raymer hunt transform (porosity/transit time relationship)
Input(s)

ø: Porosity (fraction)
Dt ma : Travel Time in Matrix (ms/ft)
Dt f : Travel Time in Liquid/fluid (ms/ft)

Output(s)

Dt: Total Travel Time (ms/ft)